Showcased here is an unpainted Darkseid hardcopy head from the 2nd series line. The piece is cast in a green resin commonly referred to as "dynacast". This hardcopy head is nice looking since it is fairly large in size when compared to the size of the superhero's heads.
Hardcopies are produced using a silicon mold (this mold is created from the original wax figure sculpting). Once it is removed from the mold it may serve a number of purposes. It might remain unpainted and ultimately used to create the steel tooling for the figures. Extra hardcopies are poured as a precaution, should something happen to the tooling master. These extras would remain unpainted as well. If a hardcopy is not destined for tooling or backup, then it will more than likely be handpainted for use in catalog photography, trade shows, or as a paintmaster. Most paintmasters for the Super Powers line are cast in milky white proto plastic (commonly referred to as internal first shots), but I have seen dynacast paintmasters.